This application claims the benefit of Japanese Patent Application No. 2005-277314, filed on Sep. 26, 2005, which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to electronic apparatus which comprise a tilt mechanism for maintaining an extendable, display portion at a desired position relative to a main body of the electronic apparatus. The invention also relates to image forming apparatus comprising such electronic apparatus. More particularly, the invention relates to an uncomplicated and relatively inexpensive means for achieving a tilt mechanism for maintaining a display portion, provided extendably, at a desired position with respect to the main body of the electronic apparatus.
2. Description of Related Art
Printers, scanners, copy machines, telephones, facsimile machines, and similar devices have been provided with electronic apparatus, each having a display portion with a liquid crystal panel or the like. For example, when employing such an electronic apparatus as an operation panel with a display portion, the operation panel may be disposed on the upper surface of the device, to facilitate the operability of the operations keys and the visibility of the display portion.
Liquid crystal panels frequently are used in such display portions. Generally, with liquid crystal panels, the viewing angle is narrow, and the contrast and color saturation may decrease when the panel is viewed from a diagonal direction. The above-described operation panel is operated from an upper surface of the device or is operated from a front side of the device. Accordingly, if the display portion is parallel to the upper surface of the device, visibility is reduced from the front side of the device, and, on the other hand, if the display portion is parallel to the front side of the device, visibility is reduced from the upper surface of the device. To address this problem, it has been proposed to provide a display portion which is extendable with respect to the operation panel, such that the position of the display panel of the display portion may be changed arbitrarily to be parallel to the upper surface of the device or to the front side of the device. Such an electronic apparatus is equipped with a tilt mechanism which maintains the display portion in an arbitrary position.
A rotary damper has been employed as the tilt mechanism disposed at the rotating part of the display portion, such as in Japanese Unexamined Utility Model Application Publication No. H07-041078. When the rotary damper is in contact with a rotating rotor inside an operational compartment formed in the device housing, oil compounded rubber is loaded into the operational compartment, and the rotor is compressed against the oil compounded rubber by a biasing means. When the rotary shaft of the rotary damper rotates, frictional resistance develops between the rotor and the oil compounded rubber, and acts as torque control for the rotary shaft.
Another tilt damper mechanism has been proposed as a separate, tilt mechanism, such as that described in Japanese Unexamined Patent Application Publication No. H07-217642, wherein movable friction plates and fixed friction plates are inserted alternately into a shaft on the display portion side. The tilt damper mechanism then presses in the axial direction via a sliding plate between the friction plates.
Tilt mechanisms as described in Japanese Unexamined Patent Application Publication Nos. H07-041078 and H07-217642 are disposed at the display portion rotational fulcrum, namely, a display portion shaft supported by the device housing. The damper mechanism is a single unit assembled from a plurality of members in the axial direction. In order to provide such a unit at the display portion shaft, mounting space for the unit must be reserved in the vicinity of the shaft. Accordingly, if the display portion shaft is in the vicinity of the upper surface or front side of the device housing, the unit in which the damper mechanism is employed protrudes from the upper surface or front side of the device housing, the device housing is enlarged, and the appearance is undesirable.
Yet another configuration has been proposed as a separate, tilt mechanism, such as that described in Japanese Unexamined Patent Application Publication Nos. 2000-227763, 2002-100883, and 2004-053768, in which a disk-shaped member is provided on the side (i.e., rear side) of the display unit opposite the display and is compressed by a frictional elastic member disposed in the device housing.
In tilt mechanisms, such as those described in Japanese Unexamined Patent Application Publication Nos. 2000-227763, 2002-100883, and 2004-053768, a disk-shaped member centered on the display portion shaft is disposed on the rear side of the display portion, such that space is reserved to hold the disk-shaped member on the rear side of the display portion. In particular, because space is reserved in the device housing to hold the disk-shaped member protruding from the rear side of the display portion in a retracted position, it is difficult to reduce the thickness of the device housing.
In addition, in known tilt mechanisms, although frictional resistance is generated by pressing the elastic member against the rotary display portion and against the rotating member as torque for controlling the rotation of the display portion, the number of components and assembly man-hours for such elastic members and the like increase.